Coating and developing apparatus

ABSTRACT

Provided is a coating and developing apparatus composed of an assembly of plural unit blocks. A first unit-block stack and a second unit-block stack are arranged at different positions with respect to front-and-rear direction. Unit blocks for development, each of which comprises plural processing units including a developing unit that performs developing process after exposure and a transfer device that transfers a substrate among the processing units, are arranged at the lowermost level. Unit blocks for application, or coating, each of which comprises plural processing units including a coating unit that performs application process before exposure and a transfer device that transfers a substrate among the processing units, are arranged above the unit blocks for development. Unit blocks for application are arranged in both the first and second unit-block stacks. Unit blocks for application which a wafer goes through are determined depending on the layering positional relationship between an antireflective film and a resist film. An exposed wafer goes only through the unit block for development without going through any one of the unit blocks for application.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. application Ser. No.11/342,616, filed Jan. 31, 2006, now U.S. Pat. No. 7,793,609, whichclaims priority under 35 U.S.C. 119 to Japanese Application No.2005-025509, filed Feb. 1, 2005, the entire contents of both of whichare incorporated herein by reference.

TECHNICAL FIELD

The present invention relates to a coating and developing apparatus thatperforms a resist liquid coating process and a developing process afterexposure to a substrate such as a semiconductor wafer or an LCDsubstrate (a glass substrate for a liquid crystal display).

BACKGROUND ART

In fabricating a semiconductor device or a LCD substrate, a resistpattern is formed on a substrate with the use of photolithographytechnique. In order to form a resist pattern on a semiconductor water(hereinafter referred simply to “wafer”), the wafer is coated with aresist liquid to form a resist film on the wafer, the resist film isexposed with the use of photomask, and then the resist film is subjectedto a developing process. In general, the resist pattern formation iscarried out by a resist pattern forming system composed of a coating anddeveloping apparatus that coats and develops a resist and an exposureapparatus connected to the coating and developing apparatus.

JP2004-193597A discloses a coating and developing apparatus, which isschematically shown in FIG. 11. A carrier 10 holding therein pluralwafers W is carried into a carrier stage 11 in a carrier block 1A, andthe wafer W in the carrier 10 is transferred to a process block 1B by atransfer arm 12. The wafer W is conveyed to a coating unit 13A in theprocess block 1B where the wafer W is coated with a resist liquid, andthen the wafer W is conveyed to an exposure apparatus 1D through aninterface block 1C.

The exposed wafer is returned to the process block 1B where the wafer issubjected to a developing process in a developing unit 13B, and then thewafer is returned to the original carrier 10. Reference sign 14 (14 a to14 c) denotes unit stacks, each provided with a heating unit and acooling unit for heating and/or cooling a wafer W before and after theprocess performed by a coating unit 13A and/or developing unit 13B, anda transfer stage. In the process block 1B, the wafer W is transferredamong the coating unit 13A, the developing unit 13B and the unit stacks14 a to 14 c by transfer means 15A and 15B disposed in the process block1B. In this case, all the wafers are transferred according to atransferring schedule specifying the timing at which each wafer iscarried into respective units.

In the coating and developing apparatus of JP2004-193597A, since acommon transfer means transfers a wafer to units for processing a waferbefore exposure (e.g., a unit for resist film formation) and alsotransfers a wafer to units for processing a wafer after exposure (e.g.,a developing unit), it is difficult to arrange an effective transferringschedule and thus to improve the throughput. This is contrary to thedemands of improving the throughput of the coating and developingapparatus consistent with the improvement of the throughput of theexposing apparatus.

JP2001-176792A (JP3337677B2) discloses a coating and developingapparatus provided with an area for coating process and an area fordeveloping process, wherein the areas are vertically separated from eachother, and are provided therein with individual transfer means.

A certain kind of resist film requires antireflective film(s) formedover and/or under the resist film. In this case, if a unit block (i.e.,a block composed of plural processing units) for forming a resist film,a unit block for forming an antireflective film before forming theresist film, a unit block for forming an antireflective film afterforming the resist film and a unit block for developing process arestacked vertically, the total height of the coating and developingapparatus increases. Thus, it is difficult to transport the coating anddeveloping apparatus from the manufacturing maker of the apparatus tothe user. Moreover, the maintenance of the apparatus is difficult.

On the contrary, if liquid processing units such as a resist filmcoating unit and an antireflective film forming units are arranged in aplane, the footprint of the apparatus drastically increases.

DISCLOSURE OF THE INVENTION

The present invention has been made under the foregoing circumstances,and it is therefore an object of the present invention to provide acoating and developing apparatus that achieves reduction in height andlength thereof to a reasonable degree while achieving high transferringefficiency in the apparatus.

In order to achieve the objectives, the present invention provides acoating and developing apparatus comprising a carrier block, a processblock, and an interface block connectable to an exposure apparatus,wherein the coating and developing apparatus is configured to: transfera substrate carried into the carrier block by using a carrier to theprocess block; coat the substrate with a coating film including a resistfilm in the process block; send the substrate to the exposure apparatusthrough the interface block; develop the substrate, which has beenexposed and returned to the process block through the interface block,in the process block; and then transfer the substrate to the carrierblock, wherein:

(a) the process block is provided with a plurality of unit blocks eachincluding: a liquid processing unit for applying a chemical liquid ontoa substrate; a heating unit for heating a substrate; a cooling unit forcooling a substrate; and a conveyer for the unit block for transferringa substrate among those units, and wherein each of the unit blocks isprovided therein with a conveying passage extending from a carrier-blockside thereof to an interface-block side thereof;

(b) the process block is provided with a first unit-block stack formedby stacking a plurality of unit blocks and a second unit-block stackformed by stacking a plurality of unit blocks, wherein the firstunit-block stack is disposed on a carrier-block side and the secondunit-block stack is disposed on a interface-block side;

(c) intermediate stages are disposed between the first unit-block stackand the second unit-block stack such that each of the intermediatestages is disposed between unit blocks located on the same level totransfer a substrate therebetween;

(d) the first unit-block stack comprises: a unit block for bottomantireflective film formation including a liquid processing unit forapplying a chemical liquid for forming a bottom antireflective film to asubstrate before a resist liquid is applied to the substrate; a unitblock for resist film formation including a liquid processing unit forapplying a resist liquid to a substrate; and a unit block fordevelopment including a liquid processing unit for applying a developingliquid to an exposed substrate to develop the same;

(e) the second unit-block stack comprises: a unit block for resist filmformation including a liquid processing unit for applying a resistliquid to a substrate; a unit block for top antireflective filmformation including a liquid processing unit for applying a chemicalliquid for forming a top antireflective film to a substrate after aresist liquid is applied to the substrate; and a unit block fordevelopment including a liquid processing unit for applying a developingunit to an exposed substrate to develop the same;

(f) the unit block for resist film formation of the second unit-blockstack is located on the same level as that of the unit block for bottomantireflective film formation of the first unit-block stack; the unitblock for top antireflective film formation of the second unit-blockstack is located on the same level as that of the unit block for resistfilm formation of the first unit-block stack; and the unit block fordevelopment of the second unit-block stack is located on the same levelas that of the unit block for development of the first unit-block stack;

(g) said apparatus has processing modes including:

a first processing mode in which an antireflective film is formed on thesubstrate in the unit block for bottom antireflective film formation ofthe first unit-block stack; the substrate is transferred through anintermediate stage corresponding to said unit block for bottomantireflective film formation of the first unit-block stack to the unitblock for resist film formation of the second unit-block stack; and inwhich unit block a resist film is formed on the substrate; and

a second processing mode in which a resist film is formed on thesubstrate in the unit block for resist film formation of the firstunit-block stack; the substrate is transferred through an intermediatestage corresponding to said unit block for resist film formation of thefirst unit-block stack to the unit block for top antireflective filmformation of the second unit-block stack; and in which unit block anantireflective film is formed on the substrate.

In one preferred embodiment, the coating and developing apparatusfurther includes a vertically-movable transfer device for transferring asubstrate between the unit block for resist film formation of the secondunit-block stack and the unit block for top antireflective filmformation of the second unit-block stack, wherein said apparatus has athird processing mode in which: an antireflective film is formed on thesubstrate in the unit block for bottom antireflective film formation ofthe first unit-block stack; the substrate is transferred through anintermediate stage corresponding to said unit block for bottomantireflective film formation of the first unit-block stack to the unitblock for resist film formation of the second unit-block stack; in whichunit block a resist film is formed on the substrate; from which unitblock the substrate is transferred via the vertically-movable transferdevice to the unit block for top antireflective film formation of thesecond unit-block stack; and in which unit block a top antireflectivefilm is formed on the substrate.

In one preferred embodiment, the coating and developing apparatusfurther includes a vertically-movable transfer device for transferring asubstrate between the unit block for bottom antireflective filmformation of the first unit-block stack and the unit block for resistfilm formation of the first unit-block stack, wherein said apparatus hasa fourth processing mode in which: an antireflective film is formed onthe substrate in the unit block for bottom antireflective film formationof the first unit-block stack; from which unit block the substrate istransferred via the vertically-movable transfer device to the unit blockfor resist film formation of the first unit-block stack; in which unitblock a resist film is formed on the substrate; the substrate istransferred through an intermediate stage corresponding to said unitblock for resist film formation to the unit block for top antireflectivefilm formation of the second unit-block stack; and in which unit blockstack a top antireflective film is formed on the substrate.

One of the unit block for development of the first unit-block stack andthe unit block for development of the second unit-block stack may bereplaced with a unit block for inspection including an inspecting unitfor inspecting a surface of a substrate and a conveyer for the unitblock for transferring a substrate between the inspecting unit and anintermediate stage.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a schematic top plan view of a coating and developingapparatus in a first embodiment of the present invention;

FIG. 2 is a schematic perspective view of the coating and developingapparatus shown in FIG. 1;

FIG. 3 is a schematic longitudinal cross-sectional view of the coatingand developing apparatus shown in FIG. 1;

FIG. 4 is a schematic perspective view showing the structure of one unitblock in the coating and developing apparatus shown in FIG. 1;

FIG. 5 shows a schematic top plan view and a schematic cross-sectionalview of a coating unit shown in FIG. 4;

FIG. 6 is an explanatory drawing showing the flow of a wafer in thecoating and developing apparatus shown in FIG. 1;

FIG. 7 is a schematic longitudinal cross-sectional view of a coating anddeveloping apparatus in a second embodiment of the present invention;

FIG. 8 is a schematic top plan view of a coating and developingapparatus in a third embodiment of the present invention;

FIG. 9 is a schematic longitudinal cross-sectional view of the coatingand developing apparatus shown in FIG. 8;

FIG. 10 is a schematic longitudinal cross-sectional view of a coatingand developing apparatus in a fourth embodiment of the presentinvention; and

FIG. 11 is a schematic top plan view of a conventional coating anddeveloping apparatus.

DESCRIPTION OF REFERENCE SIGNS

-   W: Semiconductor wafer-   20: Carrier-   C: Transfer arm-   S1: Carrier block-   S2: Process block-   S3: Interface block-   S4: Exposure apparatus-   A1 to A7: Main arm-   31: Coating unit-   41: First unit-block stack-   42: Second unit-block stack-   TRS6 to TRS8: Intermediate stage-   61: Transfer arm (Vertically-movable transfer device)-   62: Interface arm (Vertically-movable transfer device)-   63: Transfer arm (Vertically-movable transfer device)-   50: Control unit-   B1 to B7: Unit block

BEST MODE FOR CARRYING OUT THE INVENTION

A first embodiment of the coating and developing apparatus according tothe present invention will be described with reference to FIGS. 1 to 6.In the first embodiment, the coating and developing apparatus accordingto the present invention is connected to an exposure apparatus and isconstituted as a part of a resist pattern forming system. For theconvenience of the explanation, the positive X-direction in the drawingsis referred to as left direction; the negative X-direction is referredto as right direction; the positive Y-direction is referred to as frontdirection; and the negative Y-direction is referred to as reardirection. As shown in FIG. 1, the coating and developing apparatusincludes: a carrier block S1 for receiving and delivering ahermetically-closed carrier 20, holding plural (e.g., 13) wafers W(i.e., substrates) therein, into and from the coating and developingapparatus; a process block S2 for performing a coating process and adeveloping process to the wafers W; and an interface block S3. Thecoating and developing apparatus is connected to an exposure apparatusS4 via the interface block S3.

The carrier block S1 is provided with: a stage 21 adapted to hold pluralcarriers 20 thereon; openings formed in a wall in front of the stage 21;and a transfer arm C for removing a wafer W from the carrier 20 throughthe opening. A shutter is assigned to each of the openings 22 to closethe same. The transfer arm C is capable of moving toward and away fromtransfer stages TRS1, TRS2 and TRS 3 (described later), or moving inY-directions; moving vertically; rotating about a vertical axis; andmoving along the carrier arranging direction, or X-directions, in orderto transfer a wafer W to and from the transfer stages TRS1, TRS2 and TRS3.

The process block S2 enclosed by an enclosure is connected to thecarrier block S1 at the front end of the process block S2. The processblock S2 includes a first unit-block stack 41 disposed near the carrierblock S1 and a second unit-block stack 42 disposed near the interfaceblock S3. Each of the unit-block stacks are constituted by stackingplural unit blocks vertically, which will be described later. Each ofthe unit blocks is provided therein with a wafer transfer passage(transfer area) extending linearly from the process block S2 side to theinterface block S3 side.

The first unit-block stack 41 is constituted by stacking: a unit blockfor development (DEV layer) B1 for applying a developing liquid to anexposed wafer W to perform a developing process; a unit block for resistfilm formation (COT layer) B2 for coating a wafer W with a resistliquid; and a unit block for bottom antireflective film formation (BCTlayer) B3 for coating a chemical liquid for forming a bottomantireflective film on a wafer before coated with a resist liquid,wherein these unit blocks B1, B2 and B3 are stacked in that order fromthe bottom. The second unit-block stack 42 is constituted by stacking: aunit block for development (DEV layer) B4 for applying a developingliquid to an exposed wafer W to perform a developing process; a unitblock for top antireflective film formation (TCT layer) B5 for coating achemical liquid for forming a top antireflective film on a wafer aftercoated with a resist liquid; and a unit block for resist film formation(COT layer) B6 for coating a wafer W with a resist liquid, wherein theseunit blocks B4, B5 and B6 are stacked in that order from the bottom.Note that the term “layer” and the term “unit block” has the samemeaning, and that either one of these terms are used hereinafterdepending on the circumstances for the sake of convenience ofexplanation. The DEV layer B1, the COT layer B2 and the BCT layer B3 arepositioned at the same level as those of the DEV layer B4, the TCT layerB5 and the COT layer B6, respectively.

Intermediate stages TRS6, TRS7 and TRS8, serving as transfer stages, arearranged between the first unit-block stack 41 and the second unit-blockstack 42. The intermediate stages TRS6, TRS7 and TRS8 are arranged atpositions respectively corresponding to the unit blocks B1, B2 and B3(B4, B5 and B6); in other words, each of the intermediate stages TRS6,TRS7 and TRS8 are arranged at a position to and from which each of mainarms (described later) provided in the corresponding unit blocks cantransfer a wafer W. The intermediate stages TRS6, TRS7 and TRS8 arestacked vertically to constitute a unit stack U6.

Next, the structure of the unit blocks B1 to B6 will be described. Eachof the unit blocks B1 to B6 includes: a liquid processing unit (i.e.,coating unit, described later) for applying a chemical liquid to a waferW; various heating unit(s) and cooling unit(s) that performs apre-treatment and a post-treatment for the treatment performed by theliquid processing unit; a main arm (A1 to A6) that transfers a wafer Wbetween the liquid processing unit and the heating and cooling units.

Among the unit blocks B1 to B6, the positional relationship among theliquid processing unit, the heating and cooling units and the main armis the same. In other words, among the unit blocks, the positionalrelationship among the wafer-mounting positions (e.g., the centerposition of the spin chuck (described later) of the liquid processingunit, and the center positions of the heating (or cooling) plates of theheating (or cooling) units are the same.

The structure of the unit block will be described taking the COT layerB2 shown in FIGS. 1 and 4 as an example. Provided at the center in theCOT layer B2 is a wafer transfer area (i.e., transfer passage) R1extending in the front-and-rear direction (i.e., Y-direction). Arrangedon the right side of the transfer area R1 is a coating unit 31, as theliquid processing unit, having plural coating portions for coating aresist. Arranged on the left side of the COT layer B2 are four unitstacks U1, U2, U3 and U4, which are aligned in the front-and-reardirection. Each of the unit stacks is composed of vertically-stacked twoheating and/or cooling units for performing a pre-treatment and apost-treatment for the treatment performed by the coating unit 31. Thetransfer area R1 is defined between the coating unit 31 and the unitstacks U1 to U4. Clean air is sprayed to the transfer area R1 and isdischarged therefrom, thereby to prevent particles from being suspendedin the transfer area R1.

As shown in FIG. 4, the foregoing processing units for performing thepre-treatment and the post-treatment includes: a cooling unit (COL2) foradjusting the temperature of a wafer W to a designated value before thewafer W is coated with a resist liquid; and a heating unit (CHP2), or aso-called, pre-baking unit, for heating a wafer W after coated with aresist liquid. The processing units such as the cooling unit (COL2) andthe heating unit (CHP2) are enclosed by respective processing containers52. The side of each processing container 52 facing the transfer area R1is provided therein with a wafer carrying-in-and-out port. Each of theunit stacks U1 to U4 are constituted by stacking the processingcontainers 52. As shown in FIG. 1, each heating unit (CHP2) includes aheating plate 53, and a cooling plate 54 which also functions as atransfer arm. The processing units constituting the unit stacks U1 to U4includes a hydrophobizing unit (ADH2) that performs a hydrophobizingtreatment by supplying the wafer surface with an organic gas in order toimprove the adhesion of the resist film to the wafer surface.

The main arm (conveyer) A2 disposed in the transfer area R1 is capableof: moving toward and away from each processing units in the COT layerB2, or moving in X-direction; moving vertically; rotating about avertical axis; and moving in Y-direction, so that the main arm A2 cantransfer a wafer W to and from any one of the processing units in theCOT layer B2, the transfer stage TRS2 and the intermediate stage TRS 7.

As shown in FIGS. 1 and 3, a unit stack U5 is arranged between thecarrier block S1 and the first unit-block stack 41. The unit stack U5comprises transfer stages TRS1, TRS2 and TRS 3, which are stackedvertically. Two transfer stages TRS1, two transfer stages TRS2 and twotransfer stages TRS3 are provided in correspondence to the unit blocksB1, B2 and B3, respectively. The main arm (A1 to A3) in each unit blockcan transfer a wafer W to and from the corresponding transfer stages.The transfer arm C is capable of transferring a wafer W to and from anyone of the transfer stages TRS1 to TRS3 constituting the unit stack U5.

A unit stack U7 is arranged between the second unit-block stack 42 andthe interface block S3. The unit stack U7 comprises transfer stagesTRS9, TRS10 and TRS11, which are stacked vertically. Two transfer stagesTRS9, two transfer stages TRS10 and two transfer stages TRS11 areprovided in correspondence to the unit blocks B4, B5 and B6 of thesecond unit-block stack 42, respectively. The main arm (A4 to A6) ineach unit block can transfer a wafer W to and from the correspondingtransfer stages.

As shown in FIG. 1, the process block S1 is provided with a transfer arm(transfer means) 61 near the unit stack U7. The transfer arm 61 iscapable of: moving toward and away from the transfer stages TRS10 andTRS11, or in X-direction; and of moving vertically, so that the transferarm 61 can transfer a wafer W to and from the transfer stages TRS10 andTRS11. The transfer arm 61 has a function of transferring a wafer,having been transferred from the COT layer B6 to the transfer stageTRS11, to the transfer stage TRS10 corresponding to the TCT layer B5,which will be described later.

The exposure apparatus S4 is connected to the front side of the unitstack U7 of the process block S2 via the interface block S3. Theinterface block S3 is provided therein with an interface arm 62 totransfer a wafer W between the unit stack U7 of the process block S2 andthe exposure apparatus S4. The interface arm 62 serves as a wafertransfer means interposed between the process block S2 and the exposureapparatus S4. The interface arm 62 is capable of: moving toward and awayfrom the transfer stages TRS9 to TRS11, or moving in Y-direction; movingvertically; and rotating about a vertical axis, so that the interfacearm 62 can transfer a wafer W to and from any one of the transfer stagesTRS9 to TRS11 of the unit stack U7.

When a wafer W is transferred from the COT layer B6 to the TCT layer B5,it is advantageous, in view of reducing the load of the interface arm62, that the wafer is transferred from the stage TRS11 to the stageTRS10 by means of the transfer arm 61. In spite of the above, thetransfer arm 61 may be omitted; and a wafer W may be transferred fromthe stage TRS11 to TRS10 by means of the interface arm 62.

Next, the other unit blocks will be briefly described. As previouslydescribed, the DEV layer B1, the DEV layer B2, the BCT layer B3 and TCTlayer B5 have essentially the same structure as that of the COT layer B2and the COT layer B6. The DEV layer B1 and the DEV layer B2 aredifferent from the BCT layer B3 and TCT layer B5 in the followingrespects: the chemical liquid used in the coating unit 31, or the liquidprocessing unit (a chemical liquid for antireflective film formation isused in the BCT layer and the TCT layer; while a chemical liquid fordevelopment, or a developing liquid is used in the DEV layer); the wayhow the chemical liquid is applied; and the process conditions in theheating and cooling units. The DEV layer B1 are the DEV layer B2 are thesame as the BCT layer B3 and TCT layer B5 in that the main arm (A1, A3,A4, A5) assigned to each unit block (layer) transfers a wafer W betweenthe processing units of the unit block, and transfers a wafer W to andfrom the transfer stages or the intermediate stages of the unit stackU5, U6 and U7. Note that, in the TCT layer B5 and the COT layer B6 ofthe second unit-block stack 42, in order to expose only the edge portionof a wafer W prior to the exposure process to be carried out aftercompletion of the processes performed in these layers, an edge exposureunit (WEE) is incorporated into the unit stack U4 of each of theselayers.

Next, the coating unit 31 will be briefly described with reference toFIG. 5. The coating unit 31 has plural (in the illustrated embodiment,three) coating portions 301, 302 and 303, which are enclosed in a commonprocessing container 300. These coating portions are mounted on a commonbase 304 and are aligned in front-and-rear direction (Y-direction).

The coating portions 301, 302 and 303 have the same structure, and thusthe structure thereof will be described taking the coating portion 301as an example. Reference numeral 305 denotes a spin chuck, or asubstrate holder. The spin chuck 305 is adapted to hold a wafer Whorizontally by suction. The spin chuck 305 is capable of rotating abouta vertical axis and moving vertically by means of a driving mechanism. Acup 307 surrounds the spin chuck 305. A drainage system 308 including anexhaust pipe and a drainage pipe is disposed on the bottom of the cup307. Reference numeral 309 denotes a side rinse mechanism for supplyinga rinse liquid to the peripheral edge portion of a wafer W held by thespin chuck 305. The side rinse mechanism 309 is capable of movingvertically and rotating about a vertical axis.

Reference numeral 310 denotes a common supply nozzle (chemical liquidnozzle) for supplying a coating liquid to the three coating portions301, 302 and 303. The supply nozzle 310 is capable of moving along aguide rail 311 extending in the longitudinal direction (i.e., thefront-and-rear direction, or Y-direction) of the processing container300 from a position outside the cup 307 of the coating portion 301 onone end to a position outside the cup 307 of the coating portion 301 onthe other end. The supply nozzle 310 is also capable of movingvertically. Thus, the supply nozzle 310 is capable of supplying a resistliquid to any one of the center portions of wafers W held by the spinchucks 305 of the coating portions 301 to 303. Reference numeral 313denotes a stand-by area for the supply nozzle 310 disposed outside thecoating portion 301 on one end.

Reference numeral 314 denotes a filter unit mounted on the ceiling ofthe processing container 300; and reference numeral 315 denotes anexhaust unit mounted on the bottom of the processing container 300. Theatmosphere in the processing container 300 is discharged by means of theexhaust unit 315 at a predetermined flow rate while clean air whosetemperature and humidity are controlled is supplied into the processingcontainer 300 through the filter unit 314 at a predetermined flow rate,whereby clean-air downflow is formed in the processing container 300 andthe pressure in the processing container 300 is maintained at a valueslightly higher than that in the transfer area R1 for the main arm A2.Reference numeral 316 denotes wafer carrying-in-and-out ports which areformed in the side, facing the transfer area R1, of the processingcontainer 300. The carrying-in-and-out ports 316 correspond to thecoating portions 301, 302 and 303, respectively.

At the coating unit 31, a wafer W is carried into the processingcontainer 300 through a carrying-in-and-out port 316, and is transferredto the spin chuck 315 of one of the coating portions 301, 302 and 303.The supply nozzle 310 supplies a resist liquid onto the center portionof the wafer W and the spin chuck 305 rotates, whereby the resist liquidspreads in radial directions of the wafer W and thus a liquid film ofthe resist is formed on the surface of the wafer W. The wafer W, onwhich the liquid film of the resist is thus formed, is carried out ofthe coating unit 31 through the carrying-in-and-out port 316.

With the coating unit 31, as three coating portions 301 to 303 isarranged in one common processing container 301, the process atmospheresin respective coating portions are the same. Thus, one supply nozzle 310may be shared by the three coating portions to supply these coatingportions with a resist liquid. The arrangement achieves reduction in thetotal number of the component parts and the footprint of the coatingunit, as compared with the case where each of the coating portions 301to 303 has individual processing container 300 and supply nozzle 310.

Referring back to FIG. 1, the coating and developing apparatus has acontrol unit 50. Processing modes of the coating and developingapparatus can be specified by the control unit 50. The term “processingmode” may be regarded as a set of units which a wafer W sequentiallygoes through when the wafer W is transferred through the process blockS2. Specifying of the process mode may be executed by: (i) sequentiallyspecifying (inputting) the units which a wafer W should sequentially gothrough; (ii) sequentially specifying (inputting) the unit blocks whicha wafer W should sequentially go through; or (iii) selecting a desiredprocess type from the process menu. In the case (iii), a set of units(or unit blocks) which a wafer W should go through are determinedbeforehand in correspondence to respective process types; upon selectinga process type from the process menu, a set of units, which a wafer Wshould sequentially go through when the wafer W is transferred, isautomatically specified. The control unit 50 may have the followingfunction: even if a certain unit block is selected to process a certainwafer W, in a case where the process schedule in a certain unit of saidcertain unit block for processing said certain wafer W overlaps theprocess schedule for another wafer W, the control unit 50 automaticallydesignates another unit in said certain unit block having the samefunction as that of said certain unit in order to process said certainwafer W.

The process modes may be illustrated as follows:

(1) Process mode M1 in which a wafer W is transferred to the BCT layerB3 of the first unit-block stack 41, and the COT layer B6 of the secondunit-block stack 42, in that order;

(2) Process mode M2 in which a wafer W is transferred to the COT layerB2 of the first unit-block stack 41, and the TCT layer B5 of the secondunit-block stack 42, in that order;

(3) Process mode M3 in which a wafer W is transferred to the BCT layerB3 of the first unit-block stack 41, the COT layer B6 of the secondunit-block stack 42, and the TCT layer B5 of the second unit-block stack42, in that order;

(4) Process mode M4 in which a wafer W is transferred to the BCT layerB3 of the first unit-block stack 41, the COT layer B2 of the firstunit-block stack 41, and the TCT layer B5 of the second unit-block stack42, in that order;

(5) Process mode M5 in which only the COT layer B2 of the firstunit-block stack 41; and

(6) Process mode M6 in which only the COT layer B6 of the secondunit-block stack 42.

Although only the processes before exposure are described in connectionwith the process modes (1) to (6), it should be noted that the wafer Wis transferred to the exposure apparatus S4 where the wafer W isexposed, and the wafer W is transferred to the DEV layer B4 or the DEVlayer B1 where the wafer W is developed, regardless of which processmode is selected.

Next, the operation of the coating and developing apparatus will bedescribed. The description will be made assuming that the process modeM1 is selected by the control unit 50. A carrier 20 is carried into thecarrier block S1 from the outside the apparatus. A wafer W is removedfrom the carrier 20 by the transfer arm C. The wafer W is transferredfrom the transfer arm C to the transfer stage TRS3 of the unit stack U5,and then is transferred to the main arm A3 of the BCT layer B3 of thefirst unit-block stack 41. In the BCT layer B3, the wafer W issequentially transferred to the cooling unit (COL, not shown), theantireflective film forming unit (not shown) and the heating unit (CHP,not shown) in that order by the main arm A3, whereby a firstantireflective film is formed on the wafer W. Note that theantireflective film forming unit has essentially the same structure asthe coating unit 31 shown in FIGS. 1, 4 and 5; and although thearrangement of the processing units in the BCT layer B3 are not shown,those skilled in the art can readily understand the transferringoperation of the wafer W in the BCT layer B3, since the arrangement ofthe BCT layer B3 is essentially the same as that of the COT layer B2shown in FIG. 4 as previously described.

Next, the wafer W is transferred to the intermediate stage TRS8 of theunit stack U6 by the main arm A3, and then is transferred to the mainarm A6 of the COT layer B6 of the second unit-block stack 42. In the COTlayer B6, the wafer is sequentially transferred to the hydrophobizingunit (ADH, not shown), the cooling unit (COL, not shown), the coatingunit 31 (not shown) and the heating unit (CHP, not shown) in that orderby the main arm A6, whereby a resist film is formed on the wafer W. Thewafer W is further transferred by the main arm A6 to the edge exposureunit (WEE, not shown), in which the peripheral edge portion of the waferW is exposed. Thereafter, the wafer W is transferred to the transferstage TRS11 by the main arm A6, and is transferred to the exposureapparatus S4, in which the wafer W is subjected to a predeterminedexposure process. Note that although the arrangement of the processingunits in the COT layer B6 are not shown, those skilled in the art canreadily understand the transferring operation of the wafer W in the COTlayer B6, since the arrangement of the COT layer B6 is essentially thesame as that of the COT layer B2 shown in FIG. 4 as previouslydescribed. In FIG. 6, the flow of the wafer W in the process mode M1 isshown by solid arrows.

The exposed wafer W is transferred to the transfer stage TRS9 of theunit stack U7 by the interface arm 62, and is received by the main armA4 of the DEV layer B4. In the DEV layer B4, the wafer W is sequentiallytransferred to the heating nit (PEB, not shown), the cooling unit (COL,not shown), the developing unit (not shown) and the heating unit (POST,not shown) in that order by the main arm A4, whereby the wafer W issubjected to a predetermined developing process. The wafer W thusdeveloped is transferred to the main arm A1 of the DEV layer B1 throughthe intermediate stage TRS6 of the unit stack U6, and then istransferred to the transfer arm C through the transfer stage TRS1 of theunit stack U5, and is returned to the original carrier 20 placed on thecarrier block S1. Note that although the arrangement of the processingunits in the DEV layer B4 are not shown, those skilled in the art canreadily understand the transferring operation of the wafer W in the DEVlayer B4, since the arrangement of the DEV layer B4 is essentially thesame as that of the COT layer B2 shown in FIG. 4 as previouslydescribed. Instead of performing the developing process in the DEV layerB4, the wafer W may be transferred to the DEV layer B1 through the DEVlayer B4 and thus may be developed in the DEV layer B1. As thedeveloping process requires a longer processing time than theantireflective film forming process and the resist film forming process,both the DEV layers B1 and B4 are generally used.

The description will be made assuming that the process mode M2 isselected. In this case, a wafer W held in a carrier 20 is transferred tothe transfer stage TRS2 of the unit stack U5 by the transfer arm C, isreceived by the main arm A2 of the COT layer B2, and is subjected to aresist film forming process in the COT layer B2. Then, the wafer W istransferred through the intermediate stage TRS7 of the unit stack U6 tothe main arm A5 of the TCT layer B5, in which layer the wafer W issubjected to a series of process steps identical with the process stepsperformed in the BCT layer B3 in the process mode M1, whereby anantireflective film is formed on the resist film. In FIG. 6, the flow ofthe wafer W in the process mode M2 is indicated by chain-dotted arrows.Then, the wafer W is transferred to the transfer stage TRS10 of the unitstack U7, and thereafter the wafer W is subjected to the sametransferring operation and process as those in the process mode M1.

The description will be made assuming that the process mode M3 isselected. In this case, an antireflective film is formed on a wafer W inthe BCT layer B3 of the first unit-block stack 41, and subsequently thewafer W is transferred through the intermediate stage TRS8 of the unitstack U6 to the COT layer B6 of the second unit-block stack 42, in whicha resist film is formed on the wafer W. Until this point, the sameprocedure as that in the process mode M1 is performed. Then, the wafer Wis transferred to the transfer stage TRS11 of the unit stack U7, andsubsequently is transferred to the transfer stage TRS10 by the transferarm 61. Thereafter, the wafer W is received by the main arm A5 of theTCT layer B5, and an antireflective film is then formed on the resistfilm formed on the wafer W in the TCT layer B5. Then, the wafer W istransferred to the transfer stage TRS10 of the unit stack U7, andthereafter the wafer W is subjected to the same transfer operation andprocess as those in the process mode M2. In FIG. 6, the flow of thewafer W in the process mode M3 is indicated by broken arrows.

Next, the description will be made assuming that the process mode M4 isselected. In this case, although a wafer W is sequentially transferredto the BCT layer B3 of the first unit-block stack 41, the COT layer B2of the first unit-block stack 41 and the TCT layer B5 of the secondunit-block stack 42 in that order, the wafer W is subjected to the sameprocess steps as those in the process mode M3. If the process mode M5 orthe process mode M6 is selected, only the COT layer B2 or the COT layerB6 is used, and a wafer W having only a resist film formed thereon istransferred to the exposure apparatus S4.

In the foregoing first embodiment: (a) the processing units relating toa liquid process and the transfer means are integrated to form a unitblock; (b) the unit blocks relating to pre-exposure coating processes(the COT layers B2 and B6, the BCT layer B3 and the TCT layer B5) andthe unit blocks relating to post-exposure developing process (the DEVlayers B1 and B4) are vertically separated from each other; (c) the unitblocks for pre-exposure coating processes are allocated, with respect tothe front-and-rear direction, to the first unit-block stack 41 and thesecond unit-block stack 42; (d) the wafer transfer path is differentfrom each other among the case where an antireflective film is formedonly above the resist film, the case where an antireflective film isformed only under the resist film and the case where antireflectivefilms are formed both above and under the resist film. As a substratebefore exposure is transferred by a transfer means different from atransfer means for transferring a substrate after exposure in theprocess block S2, high transferring efficiency can be achieved. Theheight of the coating and processing apparatus can be reduced ascompared with the case where all the unit blocks involving the coatingprocesses are aligned in one vertical row. Thus, the maintenance of thecoating and developing apparatus can be readily performed. The footprintof the coating and processing apparatus can be reduced as compared withthe case where all the unit blocks involving the coating processes arearranged in one layer.

In addition, in the foregoing first embodiment, as the intermediatestage TRS7 or TRS8 is disposed between the unit blocks of the unit-blockstacks 41 and 42 of the same level (between B3 and B6; or between B2 andB5), a wafer W can be transferred between the unit blocks of the samelevel by means of the transfer means arranged in the respective unitblocks. Thus, the provision of a transfer means exclusively fortransferring a wafer W between the unit-block stacks 41 and 42 is notnecessary, simplifying the structure of the transfer system. In theillustrated embodiment, although only one intermediate stage TRS7 andonly one intermediate stage TRS8 are provided, each of the intermediatestages TRS7 and TRS8 may number plural to match the throughput of therespective unit blocks (between B3 and B6; or between B2 and B5) witheach other. Note that it is enough if each of the stages TRS1 to 11 isconfigured so that a wafer is can be temporarily placed thereon and themain arm can place a wafer thereon and remove a wafer therefrom.

FIG. 7 shows an essential part of a coating and developing apparatus ina second embodiment of the present invention. In the second embodiment,the exposure apparatus S4 connected to the coating and developingapparatus is an immersion exposure apparatus that exposes a wafer Wwhile a liquid film is formed on the surface of the wafer. Correspondingthereto, the coating and developing apparatus is further includes a unitblock (DCT layer) B7 having a water-shedding protective film coatingunit, or a liquid processing unit, that forms a water-sheddingprotective film on a wafer W before exposure. The DCT layer B7 isdisposed in one of the first and second unit-block stacks 41 and 42 (inthe illustrated embodiment, the second unit-block stack 42). Thewater-shedding protective film prevents the liquid from penetratingthrough the resist film during the immersion exposure process. The unitblock B7 may be provided with a cleaning unit for removing theprotective film after exposure, for removing particles adhered to thewafer W before or after exposure, and for removing components adverselyaffecting the exposure process.

In the second embodiment, a wafer W removed from the transfer stageTRS10 or TRS11 of the unit stack U7 is transferred by the interface arm62 (or the transfer arm 61) to the transfer stage TRS12, then istransferred to the main arm A7 of the DCT layer B7, and then awater-shedding protective film is formed on the wafer W in the DCT layerB7. Thereafter, the wafer W is transferred to the interface arm 62through the transfer stage TRS12, and then is transferred to theexposure apparatus S4.

FIGS. 8 and 9 show an essential part of a coating and developingapparatus in a third embodiment of the present invention. In the thirdembodiment, a transfer arm 63 is arranged adjacent to the unit stack U6between the first unit-block stack 41 and the second unit-block stack42; and the transfer arm 62 arranged adjacent to the unit stack U7 inthe first embodiment is replaced with the transfer arm 63 having thesame task as that of the transfer arm 62. The transfer arm is configuredto move vertically between a level corresponding to the uppermost unitblocks of the first and the second unit-block stacks 41 and 42 and alevel corresponding to the lowermost unit blocks of the first and thesecond unit-block stacks 41 and 42. In the third embodiment,intermediate stages in the unit stack U6 are used to transfer a wafer Wbetween unit blocks in the second unit-block stack 42 (e.g., between theCOT layer B6 and TCT layer B5) by using the transfer arm 63. To thisend, the unit stack U6 includes: two intermediate stages TRS 6 stackedup and arranged between the unit blocks B1 and B4; two intermediatestages TRS 7 stacked up and arranged between the unit blocks B2 and B5;and two intermediate stages TRS 8 stacked up and arranged between theunit blocks B3 and B6. Note that, in FIG. 9, the intermediate stagesoverlap the transfer arm 63, and are not shown for the simplicity of thedrawing.

FIG. 10 shows an essential part of a coating and developing apparatus ina fourth embodiment of the present invention. In this embodiment, thefirst unit-block stack 41 comprises a stack of a DEV layer B1 and a BCTlayer B3, and the second unit-block stack 42 comprises a stack of a TCTlayer B5 and a COT layer B6.

In the foregoing embodiments, the lowermost unit blocks of the first andsecond unit-block stacks 41 and 42 are DEV layers, but are not limitedthereto. The lowermost unit block of the second unit-block stack 42 maybe a unit block for inspection. If the exposure apparatus S4 is animmersion exposure apparatus, a cleaning unit, or a liquid processingunit, for removing a water-shedding protective film after exposure, forremoving particles adhered to the wafer W before or after exposure, andfor removing components adversely affecting the exposure process may beprovided in the lowermost unit block of the second unit-block stack 42.

If the aforementioned unit block is used as a unit block for inspection,the unit block is provided with inspection units for inspecting thewafer conditions and a main arm for transferring a wafer to and fromeach of the inspection units, in place of the heating unit and thecooling unit. Inspections to be made before exposure include aninspection of the coating film thickness and an inspection ofimpurities, for example. Inspections to be made after exposure includean inspection of overlay accuracy, for example. A unit provided in aunit block for inspection is not limited to an inspection unit, and maybe an alignment-mark detection unit or a unit for removing a part of thefilm by a laser beam process.

Concrete examples of the inspection unit to be provided in the unitblock for inspection are as follows:

-   -   a film thickness inspection unit for measuring the thickness of        a film coated on a wafer W;    -   an uneven coating inspection unit for detecting uneven coating        of a resist liquid;    -   a cleaning unit for clean a substrate before and/or after        exposure;    -   a defocusing inspection unit for detecting the offset of the        pattern occurred in the exposure apparatus;    -   a development defect inspection unit for detecting defects in        the development process;    -   a comet inspection unit for detecting comets generated on the        surface of a wafer W after coated with a resist liquid generated        due to the existence of bubbles or impurities in the resist        liquid;    -   a splash-back inspection unit for detecting splash-backs        generated due to the re-attachment of a solvent of a resist        liquid once thrown out from the wafer W surface;    -   a common defect inspection unit for detecting a common defect        appearing at the same location on wafer W surfaces and having        the same shape;    -   a scum inspection unit for detecting resist residue remaining on        a wafer W after development;    -   a No-resist/No-development inspection unit (failure inspection        unit) for detecting the failure in executing a resist coating        process and/or a development process;    -   a line-width measurement unit for measuring the line width of a        resist film formed on a wafer W; and    -   an overlay accuracy inspection unit for inspecting the overlay        accuracy between a wafer W exposed by an exposure apparatus and        a photomask by comparing it with a reference value.

The unit block for inspection may be provided at least one of the above.

The coating and developing apparatus according to the present inventionmay be such that it performs coating and developing processes to asubstrate other than a semiconductor wafer, such as a glass substrate(LCD substrate) for a liquid crystal display.

1. A coating and developing apparatus comprising a carrier block, aprocess block, and an interface block connectable to an exposureapparatus, wherein the coating and developing apparatus is configured,upon connection of said coating and developing apparatus with theexposure apparatus, to perform operations including: transferring asubstrate carried into the carrier block by using a carrier to theprocess block; coating the substrate with a coating film including aresist film in the process block; sending the substrate to the exposureapparatus through the interface block; developing the substrate, whichhas been exposed and returned to the process block through the interfaceblock, in the process block; and then transferring the substrate to thecarrier block, wherein: the process block includes a first unit-blockstack and a second unit-block stack, each of the unit-block stacksincluding a plurality of unit blocks stacked vertically, each of theunit blocks includes a transfer area extending in a first direction froma carrier-block side to an interface-block side, a plurality ofprocessing units each for processing a substrate, and a main conveyerprovided to move within the transfer area to transfer a substratebetween the processing units; the unit blocks of the first and secondunit-block stacks are arranged such that, the unit blocks of the firstunit-block stack are located at levels corresponding to the unit blocksof the second unit-block stack, respectively, and such that the unitblocks of the first and second unit-block stacks located at the samelevel are aligned in the first direction, whereby a plurality of pairsof the unit blocks, each pair including the unit blocks of the first andsecond unit-block stacks located at the same level, are made; theplurality of pairs of the unit blocks includes first pairs of the unitblocks which are each configured such that one of the first pair of theunit blocks is provided for performing processes to be performed to asubstrate earlier and the other of the first pair of the unit blocks isprovided for performing processes to be performed to the substratelater, wherein a first intermediate stage is provided between the unitblocks of each of the first pairs of the unit blocks to transfer asubstrate therebetween; and the unit blocks of each of the first andsecond unit-block stacks include a unit block including a liquidapplying unit configured to apply a processing liquid to a substrate anda heat-treating unit configured to heat-treat a substrate.
 2. Thecoating and developing apparatus according to claim 1, wherein the firstpairs of the unit blocks include a pair of the unit blocks between whicha plurality of the first intermediate stages are provided.
 3. Thecoating and developing apparatus according to claim 2, furthercomprising a first vertical conveyer provided between the firstunit-block stack and the second unit-block stack and configured totransfer a substrate between the first intermediate stages located atdifferent levels.
 4. The coating and developing apparatus according toclaim 3, further comprising: an interface-block conveyer provided in theinterface block to transfer a substrate; and a plurality of secondintermediate stages provided to transfer a substrate between the mainconveyers in the second unit-block stack and the interface-blockconveyer, wherein the second intermediate stages are arranged on aninterface-block side of the second unit-block stack and are arranged atdifferent levels corresponding to the unit blocks of the secondunit-block stack, respectively.
 5. The coating and developing apparatusaccording to claim 4, further comprising a second vertical conveyerprovided on the interface-block side of the process block and configuredto transfer a substrate between the second intermediate stages locatedat different levels.
 6. The coating and developing apparatus accordingto claim 2, further comprising: an interface-block conveyer provided inthe interface block to transfer a substrate; and a plurality of secondintermediate stages provided to transfer a substrate between the mainconveyers in the second unit-block stack and the interface-blockconveyer, wherein the second intermediate stages are arranged on aninterface-block side of the second unit-block stack and are arranged atdifferent levels corresponding to the unit blocks of the secondunit-block stack, respectively.
 7. The coating and developing apparatusaccording to claim 6, further comprising a second vertical conveyerprovided on the interface-block side of the process block and configuredto transfer a substrate between the second intermediate stages locatedat different levels.
 8. The coating and developing apparatus accordingto claim 1, further comprising a first vertical conveyer providedbetween the first unit-block stack and the second unit-block stack andconfigured to transfer a substrate between the first intermediate stageslocated at different levels.
 9. The coating and developing apparatusaccording to claim 8, further comprising: an interface-block conveyerprovided in the interface block to transfer a substrate; and a pluralityof second intermediate stages provided to transfer a substrate betweenthe main conveyers in the second unit-block stack and theinterface-block conveyer, wherein the second intermediate stages arearranged on an interface-block side of the second unit-block stack andare arranged at different levels corresponding to the unit blocks of thesecond unit-block stack, respectively.
 10. The coating and developingapparatus according to claim 9, further comprising a second verticalconveyer provided on the interface-block side of the process block andconfigured to transfer a substrate between the second intermediatestages located at different levels.
 11. The coating and developingapparatus according to claim 1, further comprising: an interface-blockconveyer provided in the interface block to transfer a substrate; and aplurality of second intermediate stages provided to transfer a substratebetween the main conveyers in the second unit-block stack and theinterface-block conveyer, wherein the second intermediate stages arearranged on an interface-block side of the second unit-block stack andare arranged at different levels corresponding to the unit blocks of thesecond unit-block stack, respectively.
 12. The coating and developingapparatus according to claim 11, further comprising a second verticalconveyer provided on the interface-block side of the process block andconfigured to transfer a substrate between the second intermediatestages located at different levels.
 13. The coating and developingapparatus according to claim 1, wherein the liquid applying unit isconfigured to apply a resist solution to form a resist film on asubstrate.
 14. The coating and developing apparatus according to claim1, wherein the liquid applying unit is configured to apply a solution toform an antireflective film on a substrate.
 15. The coating anddeveloping apparatus according to claim 1, wherein the liquid applyingunit is configured to apply a solution to form a water-repellantprotective film on a substrate.
 16. The coating and developing apparatusaccording to claim 1, wherein the liquid applying unit is configured toapply a cleaning liquid to clean a substrate.